Impulse-transmitting device



Feb. 13, 1923. 1,445,235,

" L. D. PLQTNER.

IMPULSE TRANSMITTING DEVICE.

FILED APR. 14, 1920,. 2 SHEETS-SHEET 1.

Feb. 13, 1923. 1,445,235.- L. n. PLOTNER.

IMPULSE TRANSMITTKNG DEVICE.

FILED APR. 14, 1920. 2 SHEETSSHEET 2.

Patented Feb. 13, 1923.

warren stares earner erasin LOYD n. PLOTNER, or BROOKLYN, NEW YORK, AssIenon To wnsrnmv nni crmo COMPANY, INCORPORATED, OF l YORK.

IlVIPULSE-TRANSMIT'I'ING DEVICE.

NEW YORK, N. Y., A. CORPORATION 0F NEW Application filed April 14, 1920. Serial No. 373,689.

To all whom it may concern 7 Be it known that I, LOYD D. PLorNEn, a citizen of the United States, residing at Brooklyn, in the county of Kings, State of New York, have invented certain new and useful Improvements in Impulse-Transmitting Devices, full, clear, concise, and exact description.

This invention relates to impulse transmitting devices and more particularly to an impulseetransmitting device for use at. an operators posit-ion in a semi-automatic telephone system.

T he object of this invention is to provide an impulse-transmitting device, which is simple to operate, and which will rapidly and efficiently transmit impulses and pro-v vide for the pulses.

A feature of the invention consists in the provision of a single set of digit keys, common to a plurality of impulse sending mechproper spacing between imanisms, which are adapted to be successively operated in a first movement to positions predetermined by successive actuations of any of said digit keys, and to be operated in a second movement to deliver impulses to an impulse circuit in accordance with the digits represented by the actuated keys.

A further feature of the invention is the provision of means for reducing the time required for the impulse producing mechanisms to' register the indications of the depressed keys.

The various features of the invention may he more readily understood by reference to the accompanying drawings which disclose one arrangement for embodying the invention in a sender circuit for a semi-automatic telephone system.

Referring to the drawings, Fig. 1, when placed over Fig. 2, shows so much of the system as is necessary for an understanding of the invention. Fig 1 shows a subscribers line having a station A which'may be connected in any well known manner to a cord circuit B. Accessible to the cord circuit ii there may be trunk circuits terminating in jacks such as 55 at an operators position. Connected to the jackthere may be a nonnumerical switch which may have access to the usual selectors and connectors. selector schematically represented at L having an impulse responsive relay -58 is shown. The operators of which the following is a and a solid segment position. may be provided with ten keys, 1, 2, 3, 4-, 5, 6, 7, 8, 9land- 0, respectively corresponding to the ten digits of the decimal notation. A dialing key 51 is provided in the cord circuit for connecting the impulse transmitting device to the cord circuit. A start key 53 maybe provided for initiatingthe movement of the impulse transmitting device. relays 80, 81 and 82 provide for the uniform operation of the impulse transmitting device iirdelivering the impulses. In Fig. 2 of the drawings three registers or senders are indicated as D, E, and F. These registers may be similar in construction to the structure described in an application ofForsberg and De Vignier Serial No. 317,1261filed August 13, 1919, but modified as hereafter described.

A brief description of register D will be given, registers E and F shown in the drawing being similar thereto, Fixed to a rotatable shaft (not shown) are three brushes 170, 171 and 172, and a pa-ir of cams 173 and 116 each being insulated from the'other in the usual manner. Cooperatingwith brush 170 is a contact bank having eleven contacts 106 all, strapped together. Cooperating with brush 171 .is' a contact bank havingfi contacts and a solid segment 107. all strapped together. For brush172 only 6 contacts are necessary although more than 6 are shown. The brush 172 differs from brushes 170 and 171 in that it is of. the bridgin'g'type, i. e., it makes before breaking in passing from one contact to the next. Cam 116 is so constructed that the contacts associated therewith. are operatedfas soon as the brushes of the switch have been moved one step from normal and are re stored to normal, when the brushes are restored tonormal. Caml73 is'so constructed that its contacts are opened as soon as the switch have taken one step or the other of these impulsers is included in the impulse circuit-depending upon the character of the digit-key actuated. For the purpose of this specification. brush 172 is termeda point finder. Conne'otedfto the con- A train of stepping I tacts of the bank associated with the point finder are five conductors leading to five pairs of relays associated with the set of ten digit keys. in the drawings the second contact of the pointfinder is connected to relays 30 and 25,=the third to relays 29 and 24:, the fourth to relays 28 and 23 the fifth to relays 27 and. 22 and thesixthto relays 26 and 21. If either of the first five keys of the set is actuated, relay 128 will be operated and impulserb will be included in the inipulse circuit, Whereas ifeither of the last five keys of the set is actuated,relay 128 will not be actuated and impulser a will be included in the impulse circuit. For example, if key 1 is depressed, relay 21 vill be operated and the register I) will be operated under control of a stepping magnet until the point finder rests on the sixth contact. Relay 128 will, also be operated thus includ ing'iinpulser 7) in the impulse circuit. When the start key 53 is actuated, the register will again he operated under control of magnet 121 and impulser a will deliver one impulse to the impulse circuit. It key 6 is actuated,

the register again be operateduntil the sixth. contact is reached, relay 128 will not lie operated, and impulser a will be included in the impulse. circuit. When the start key is actuated the register will be operated under control of magnet 121 and inipulser a will. deliver one plus five or six impulses.

As soon as the brushes have been moved under control of magnet 121to provide for spacing; between series of impulses, a trans "fer relay such as 114 operates to connect the succeedingregister of the train to the impulse circuit.

Having; given a detailed description oi the component parts, a description will now be given of the operation.

The subscriber at the station A having initiated a call and the answering end of the cord circuit B having been associated therewith in any well-known manner, the operator may actuate a listening key not shown) thereby connecting the operators, telephone set in circuit so that the operator may converse with the calling subscriber to ascertain the number oi? the line with which connection is desired. Assuming, for example, that number 368 is after restoring the listening key to normal, may insert calling plug 54 into jack 55, whereupon relay of the cord circuit is energized over a circuit including ground, the sleeves of jack 55 and plug 54 winding; of relay 50 and grounded battery. Relay 50 in energizing establishes a loop across the cord circuit. resulting in the operation of a non-numerical switch (not shown) at the automatic exchange in the well-known manner. The loop includes the tips of ack 55. plug B hupper normal contacts of key 51,

upper righthand winding oi? repeating coil desired. the operator 56, upper and lower alternate contacts of relay 50, lower right-handwinding'ot repeating; coil 56, winding of relay 57, lower normal contacts of key 51, and rings of plug 5 landjack55. i l

The operation oi? the nonnumerical switch may extend the calling line to an idle selector L in the well-known manner. The impulse relay 58 may respond to the impulses sent by the impulsetransmitting device in a manner now to be described and may set any switch such as L in accordance with the impulses sent.

The operator may then actuatethe dialing key 51, thus y from the calling end oi the cord circuit B and preparing the impulse transmitting device for connection to the end. actuating; the key 51, relay 02 is energized over a circuit through the normal contacts of key 53, lowermost alternate contacts ct key 51, and the winding of relay 52 to grounded battery. Relay 52 in operating establishes at its armature and contact, a loop for the selector switch, replacing the loop through the repeating; coil 56. l

The operator may then proceed to actuate keys in accordance with the number desired, which has been assumed to be 368. l iithis instance, the first key actuated will act as the hundreds digit, and a momentary depres: sionot" key 3 completescircuits for relays 23 andl120, the former extending from ground, through the lett-hand ,contacts oi key 3. winding of relay 23 to grounded battery, and the latter from ground, throughthe right-hand contacts of key 3, conductor- 31, left-hand armature and hack contact of .relay ll hright-hand normal contacts ot cam 116 and winding oi relay 120 to grounded battery. Relay 23 in attracting its outer left hand armature completesa circuit for relay "128, said circuit extending from ground, through the outer left-hand arm ature and front contact ot'relay 23, conductor 33, middle right-hand armature and back contact of? relay 11d, right-handwinding; oi? relay 128 to grounded battery. Relay 2 completes a locking circuit for itself extending from grounded battery "through the winding of relay 23, inner left-hand armature and trout contact of relay 23, conductor ?52, and inner rightdianc contact of relay ll l-to ground. Relay in operating, disronn ects llTlPlllSGI' m or the brush 170 and its associated contact bank, from the impulse circuit whiclrincludes conductor 40, and connects impulser I) or the brush 171 and its associated contact bank, thereto. Relay 120 in operating completes a circuit for motor magnet 121, saidcircuit extending" 'tlOHl grounded battery, through thewinding oi magnet .121, inner right-hand armature and trout contact of relay 120, arn z'rture and disconnecting the answering extending from ground,

l armature and baclc baclr contact of magnet 121, outer righthand arn'iature and'front contact of relay 126 to ground. Magnet 121 therefore opert i'noring the brushes 1'70, 171 and 1720f ister D from the first to the second position, thereby opening the contacts associate-d with cam 173, and opening the normal an-zi rinsing the-alternate contacts associated w th cam 11.6. soon as the alternate contacts oi? cam 116 are closed a circuit, for maintaining relay 128 energized, is compieted, said circuit extending from grounded battery thrr l the left-hand winding, t'ront contact and lert-hand armature of relay 128, and left-hand alternate contacts of cam 116 to ground. Relay 120 is maintained energized o a path including grounded batter windin of relay 120, front contact and inner left-hand armature of relay 120, l)1'11$l1 172 an d its Second contact, conductor 45, bacl: contacts and right armatures 0t. relays 30 and to round. ht otor 121 continues to operate inthe well-known manner and step the brushes until an ungrounded 1Z1) rele thereby opening the circuit of magnet 121 and bringing the switch to rest upon the terminals representing the depressed key.

In this instanceas soon as brush 172 has taken three steps and centers upon its fourthcontact, the holding circuit for relay 120 extending through brush 172 and its fourth contact. conductor 43, right-hand armature and back contact of relay 28 is opened at the right-hand armature and back contact of relay 23. thereby opening the circuit for magnet 121 and completing a circuit for relay 114. The

circuit for the energization of relay 114 may be traced from grounded battery, through resistance 115, winding of relay 114, outer left-hand armature and baclr'contact of relay 120, and left-hand alternate contacts of cam 116 to ground. Relay 114, in operating, releases relay 23 by opening the locking circuit therefor, and prepares acircuit for relay 140 controlling the motor magnet associated with the next sender.

Upon actuation of the key representing the next digit of the desired number, namely 6. circuits for relays 26 and 140 are completed, the former extending from ground, through the left-hand contacts of key 6, and

winding of relay 26 to grounded battery, and

the latter, from ground, through the righthand contacts of key 6, conductor 31, lefthandalternate contacts of relay 114 (which is maintained energized through the outer left-hand normal contacts of relay 120 and left-hand alternate contacts of cam 116), left-hand normal contacts of relay 134, right-hand normal contacts of cam 136, and

winding or" relay 140 to grounded battery.

Relay 26 upon energizing locks up over ainal. is found by brush 172, when relayv Relay 120 thereupon releases,

tuation of key circuit including its winding and left-hand contacts, conductor 32, and the inner righthand normal contacts of relay 134. Relay 140 in operating, completes a circuit for motor magnet 141 over a path similar to that described for motor magnet 121 associated with switch D. a It will be noted that relay 148 is not energized and that impulser a will be included in the impulse circuit, which includes conductor 40. Magnet 141 in operating moves the brushes 180, 181 and 182 of the register E one step, thereby com.- pleting a circuit formaintaining relay 140 energized, said circuit extending from grounded battery, through the winding of relay 140, front cont-act and inner left-hand arma: ture of relay 140, brush 182, and its second contact, conductor 45, and right-hand normal contacts of relays 30 and 25, to ground. Motor magnet 141 continues tooperate and step the brushes over the terminals until a terminal having no ground thereon is reached. In this instance, the brushes 0t register E will be moved five steps and upon reaching their sixth contact, the circuit for magnet 140 extending from grounded battery, through the left-hand alternate contacts of relay 140, brush 182 and its sixth contact, and conductor41, will-be open at the right-hand armature of relay 26. Relay 140 therefore deenergizes, and the movement of the brushes ceases; As soon as relay 140' retracts its armatures, relay 134 is energized over a circuit extending from grounded battery through resistance 135, winding of'relay134, left-hand normalcontacts of relay 140,, and left-hand alternatecontacts of cam 136 to ground, said contacts having been closed upon the first step of the switch. Relay 134, upon energization, preparesa cir-. cuit at its left-hand armature and front contact for relay 160 ot the next register, and at its inner right-hand armature and front contact, opens the locking circuit for relay 26. 1

The operator then depressesthe key representingthe next digit of the number desired, which has been assumed to be 8. Ac- 8 completes circuitstor relays 28 and 160, that of the former extending from ground, through the left-hand contacts of key 8, and winding of relay 28 to grounded battery, and that oi" the latter from groundthrough the right-hand contacts of key 8, conductor 31, left-hand alternate con-. tacts of relays 114 and 134,'let't-hand normal contacts of relay 154, normal contacts of cam 156, and winding of relay 160 to grounded battery. Relay 28, upon'energiz ing, locks up over a path including grounded battery, the Winding, left-hand armature" and front contact of relay 28, conductor 32-, inner righthand armatures and front contacts of relays 114 and 134, and inner righthand armature'and back contact otrelay through ically by the 154 to ground. Relay 160 in energizing completes a. circuit for motor magnet. 161 similar to that described. for magnet 121, whereupon the brushes 190, 191 and 192 of switch F are moved one step. Relay 160 is maintained energized in a manner similar to that previously described for relays 120 and 1 10 and the motor magnet continues step ping the brushes until the brush 192 reaches a contact on which no ground is found. In this instance, the motor magnet 161 moves the brushes three steps and when brush 192- centers on its fourth. contact, the'circuit for relay 160, extending from grounded battery,

the winding, front contact and inner left-hand armature of relay 160, brush 192 and its fourth contact, and conductor 43, is open at the contactsof relay 28. Relay 160 releases its armature thus opening the operating circuit for magnet 161 and bringing t-he register to rest. Relay 1542 then op crates over a circuit similar to that. described for relays 114i and 134, thus releasing relay 7 28. Relay 168 was not energized when key Swas actuated and the impulse circuit now includes impulser e and ground at the righthand armature of relay 168.

The operator then depresses key 53 which may be restored to normal. electromagnetmagnet 70. -The arrangement of the key and magnet may be similar to that shown in Patent No. 555,707 of March 3, 1896, to J, J. OConnell- Tn actuating key 53, acircuitis con ipleted at the lefthand alternate contacts thereof for relay 71. Through the righ'tha nd alternatecontacts of key conductor 40, extending to the registers D, E and F, is connected to the relay 52. Relay 71 in operating connects ground to a circuit for a train of relaysSO,

81 and 82, which govern the movement of the registers in the r impulse producing,

movement, and connects battery to the windings of relays 117, 137 and 157. Relays 117, 137 and 157 do not energize at this time, however, due to their circuits being open at the cams of their associated senders. Belay 80 is operated. over a circuit extending from. ground, contact of relay 71, outer left-hand armature and back contact of relay 82, and winding of rclay. 80 togrounded battery. Relay 80 in operating completes a circuit, atits armature and front contact,for relay 81. Relay 81 in operating completes a circuit, through its al.- ternatecontacts, for relay 82, \\l 'ch locksup over, a'circuit extending from grounded battery, through the winding, front contact and..-

inner armature of relay S2, conductor 75, inner left -hand armature and back contact of relay 117,-back contact and outer rightehand armature of relay 120, contacts of magnet 121, back contact and outer left-hand armature of relay 117, conductor 7 3, and front contact and inner leftrhand armature of reinner. left-hand armature and front mana e lay 71 to ground Relay 82, in operating, opt s the le n3 opens the circuit for rel-a1 81.. Bela circuit for relay 80, which in re-.

81 in releasin com let-es a circuit for-motor back contact of relay 120, back contact and middle left-hand armature of relay 117,.

conductor '7 middle armature and front contactof relay 82, normal contacts of relay 81, and front contact and inner left-hand armature of relay 71 to ground. Magnet 121, in operating, moves the brushes of switch D one step and opens the lockingcircuit for relay 82, which releases its armatures. When the brushes of switch D are moved one step, the impulse circuit, extending from grounded battery, through. the winding of relay 52, lowermost cont-acts of key 51, right-hand alternate contacts of key conductor 40, fourth contact and brush 171 of switch D, front contact and righthand arniiature of relay 128, sixth contact and brush 180 of switch E, right-hand armature and back contactof. relay 14:8, fourth contact and brush 190 of switch F and back contact and armature of relay 168 toground, is interrupted as brush 171 passes from its fourth to the fifth contact. The cycle. of operations heretofore. and continues until the brush 171 has.

reached the solid segment 107 at which time the circuit for relay 52 willhave been interrupted three times resulting in three impulses being sent to the impulse responsiye relay 58.

described is repeated:

Under control of the stepping relays, the

motor magnet 121 will continue stepping the brushes of switch'l) after the first series of impulses has been sent, (but the impulse circuit will not be interrupted) until the circuit for. relay 117 is closed at, the contacts of cam 17 8. Relay 117 in operating momentarily opens theconductors 73, 74- and 75 thereby,deenergizing the relays 8( 81 and 82' and associating said relays with the second register E. The circuit for relay 117 is closed over a path extending from ground, through contacts of cam 173,:windingot rel a armature. and front contact. of relay 71 to grounded battery; Relay 80, and in turn relays 81 and 82,.immediately .deenergize.

As soon as relay. 117 attracts its armaturcs a circuit for motor magnet 14-1 is completed, and c'1rcu1t extending from grounded batthrough the winding of magnet 14:1,

tcry, inner right-hand armature and back contact of relay 1 10, back contact. and middlelefthand armature of relay 137, front contact and middle left-hand armature ofrelay 117,

i 117, conductor 72, and left-hand attracting to normal position hand armature of relay 71 to ground; As soon as magnet; 1451. operates, the locking circuit for relay 82 is opened whereuponrelays and 81 again energize. Relay 82 then operates thus releasing relays 80 and 81 whereupon the motor magnet again operates to move the brushes another step. This operation. continues until six steps have been taken and six impulses have been. sent to the impulse responsive relay 56. Under control of the stepping relays, magnet 1 -11 continues to step the brushes until the contacts of cam 183 are closed. As soon as the contacts of cam 183 are closed, a circuit for relay 137 is completed, said circuit extending from. ground through contacts of cam 183, Wl11(l ing of relay 137, conductor 72, outer lefthand arn'iatm'e and front contact of relay 71 to grounded battery.

Relay 137 in operating prepares a circuit for stepping magnet 161 and in a manner similar to that previously described for magnet 14:1, the brushes of register I are stepped until the contacts of cam 193 are closed. A circuit for relay 157 is thus established from ground, through contacts of cam 193, winding of relay 157, conductor 72, outer left-hand armature and front contact of relay 71 to grounded battery. Relay 157, in its armatures, disconnects the stepping magnet 161 from the stepping relays, and completes a circuit at its right- .hand armature for the .energization of relays 118, 138 and 158 in parallel. Relay 118 in attracting its armature completes a circuit for relay 120,- said circuit extending from ground, through the armature and front contact of relay 118, right-hand alternate contacts of earn 116, and winding of relay 120 to grounded battery. Relay 120, upon energization, completes a circuit for motor magnet- 121, previously described, which operates to restore the brushes of sender D to normal. Upon reaching normal position, the contacts of cam 116 are restored resulting in the opening of the circuit for relays 128, 1.20 and in turn the opening of the operating circuit for magnet 121. In a similar manner the brushes of senders E and are restored to normal. hen thebrushes of all switches have reached normal position, a circuit for release magnet 70 is completed, said circuit extending from ground through the back contacts and outer right-hand arn'iatures of relays 154, 1341 and 11 1, conductor 34, front contact and right-hand armature of relay 71 and winding of magnet 70 to grounded battery. Upon energization, magnet 7O may restore the key 53 to normal. As soon as the key 53 returns to normal the operator may restore the dialing key 51 to normal and the sender is ready for the next call.

If the operator desires to restore the automatieally she may .ivl 11 ch switches to normal before they are restored actuate thekey which connects ground, through conductor 76 to relays 118, 138 and 158 thereby causing such switches that are not on normal posi tion to return to normal in the manner pre viously described. Actuationozt key also completes a circuit for release. magnet 70, uponcnergization restoreskey 53 to normal, said circuit extending from grounded battery, through the winding of magnet 1'0, right-hand armature and front contact of relay 71., conductor 34, andouter righthand :armatures and back contacts of relays 11.1, .134 and 1541 to ground. i

It will be noted that with. the. arrangement of apparatus and circuits, only as many senders are actuatedas keys are de pressed. F or example, actuation of onekey actuates sender D, actuation ofmtwo, keys actuates senders I) and E, etc. ingthe start key, afterthe digit keys have been actuated in of impulses would be sent over the impulse circuitcorresponding to the digits 'setup in the sender. Although means are shown in the drawings for sendingimpulses for numbers having a maximum of'three digits only, itis obvious that other registers havr mg circuit arrangements ident cal withthat of D and E may bGlIltGIPOSBCl between-registersE and F, thus providing a. device capable of sending impulses for having more than three digits.

What is claimed is: 1. In animpulse transmitting device, the combination with a single set of digit keys and an impulse responsive means, of an electromagnetic step-by-step mechanism adaptnumbers ed to register the indication of any key .when actuated, and thereafter independently of the actuated key to actuate said impulse responsive means.

2. In an impulse transmitting device, the

combination of a single set of digitrkeys, electromagnetic stepby-step mechanism common to said keys, adapted in one movement to register the indication of any of said keys when depressed, impulse res 'ionsive means operating under the control ofv said mechanism during a subsequent movement thereof, and means for thereafter restoring said-mechanism to normal. p

3. In an impulse transmitting; device the combination with a single set of digit keys and a selector, of. electromagnetic step-bystep mechanism common to saidkeys adapted to register the indications of a plurality of said keys when act'uated,, and thereafter during .a 'subsequentmovement to cause the operation of said selector.

4. In an impulse transmlttmg devlce, the combination of a single set of digit keys, electromagnetic stepby-step mechanism, op-n crating in a first movement to register the By 'operat each case, a; number 'sllCfl one of an of said keys when actua l, unpulse responsive means operating under control of impulses transmitted by said mechanism in a second movement, and means for automatically restoring said mechanism to normal in a third movement.

5. In an impulse transmitting device, a plurality of keys each representing a dititerent digit oi the decimal system of notation, a plurality of registers, one

for each digit of the highest number designed to be signaled, said registers having contacts corresponding to said keys, means responsive to the successive actuation of any of said keys for successively setting the registers to points predetermined by the keys actuated, an impulse circuit, and means for causing the further movement oi said registers to transmit impulses over said impulse circuit in accordance with digits represented by the actuated keys.

6. In an impulse transmitting device, a single set of digit keys, a register adapted tomove in one stage to register the indication of either one of two keys of said set, a pair of impulsers associated with said regi'ster, an impulse circuit, and means for moving said register in a second stage to deliver impulses to said impulse circuit from one or theother of said impulsers depending upon the' character 01": the digit.

7. In an impulse transmitting device, an impulse circuit, asingle set of digit keys, a register having a pair of impulsers associated therewith, means responsive to the actuation of anykey for causing said register to-move in a first stage to a position predetermined by a'key when depressed and for including one or the other of said impulsers in said impulse circuit, and means for causing said register to move in a second stage to deliver impulses in accordance with the digit key depressed.

8. In an impulse transmitting device, a single set of digit keys, a plurality of registers capable of movement in three stages, means responsive to the successive actuation of'any of said keys for successively moving said registers in their first stage, means for causing the further movement of said registers in their second stage, impulse 'respons'ive meansresponsive to the extent of the movement oi the registers in their second 'stage,and means for restoring said registers to normal in their third stage.

9,111 an impulse transmitting device, a. single set of digit keys, a switch having a point finder and a pair of impulsers associtherewith, an impulse 'cricuit, means actuation of any of said said switch to cause said point predeterresponsive to the keys for operating point finder to 'move to a mined by the actuation of said actuated key and for including one or the other of said impulsers in said impulse circuit, and means for operating said switch in a further movement to cause said impulse circuit to be interrupted by said impulsers a number of times corresponding to the digit represented by the actuated key.

10. In an impulse transmitting device, a single set oi digit keys, each representing a different digit of the decimal tion, a plurality oi": registers controlled by said keys, one register being provided for each digit place of the highest number designed to be signaled, means responsive to the successive actuation of any oi said keys for moving in a first movement as many-oi said registers to predetermined positions as keys have been actuated, means for locking said registers in the positions to which they have been moved, an impulse circuit, means for successivelymoving said registers in a second movement, and impulse responsive means actuated by said registers in their second movement.

11. In an impulse transmitting device, a single set of digit keys, each representing a different digit of the decimal system of notation, a plurality of switches controlled by said keys, one switch each digit place of the highest number designed to be signaled, means responsive to the successive actuation of any oi said keys for moving in a first movement as many of said switches to predetermined positions as keys have been actuated, means for locking said switches in the positions to which they been moved, an impulse circuit, means for successively moving said switches in a secsystem of notabeing provided. for i end movement, impulse responsive means actu'ated by said switches in their second move ment, and means for restoring said switches to normal in a third movement.

12. In an impulse transmitting device, a set of ten digit keys, a relay for each key responsive to the actuation of its associated key, said relays being grouped in pairs, a register adapted to be set in one of a plurality of positions in response to the actuation of either one of a pair of such relays, apair of impulsers associated with said register for subsequently producing impulses, aswitching relay controlled by one relay of the pair of said first mentioned relays, and means controlled jointly by said switching relay and the set position of said register for determining the number of impulses to be produced.

In witness whereof, I hereunto subscribe my name this 10th day of April A. 1)., 1920. 

